text: When an Arabidopsis plant is subjected to cold temperatures, it induces cold response genes. In order for cold genes to be expressed, COLD1 receptors that are present on the plants surface sense the cold temperature and activate Ca channels, these channels include: MCA1, MCA2 and other undetermined channels. The activation of Ca channels allows for Ca to move into the cell and increase cellular Ca concentration. The concentration and duration of Ca within the cell is determined by the plants acclimation to the temperature, as well as the intensity and length of cold duration. During increased Ca concentrations, Ca is used as a second messenger to increase the concentration of Ca dependent protein kinase (CPKs). During times of increased Ca concentrations, Ca also binds to calmodulin on the CRLK and AtSR1/CAMTA3. Activation of the CRLK causes an MAPK cascade that activates the MAPK pathway, signaling for the suppression of ICE1 degradation: ICE1 encodes a transcription factor that promotes production of CBF/DREB genes. AtSR1 also binds to the promoter region of CBF and promotes CBF gene expression. CBF and DREB transcription proteins are then synthesized and bind to the promoter of cold induced genes DRE and CRT. Binding to the promoter region of the cold induced genes increases the rate of transcription of cold genes, allowing the Arabidopsis plant to become more acclimated to the cold. This Ca signaling cascade, and transcription of cold genes in response to cold temperatures, allows for the plants survival.